Have you ever had a “gut feeling” about something? Or felt butterflies in your stomach when you were nervous? The connection between our brain and our gut is a complex one that scientists are still trying to fully understand.

But what we do know is that there is a direct link between the two, known as the “gut-brain axis.”.

What is the Gut-Brain Axis?

The gut-brain axis is a bidirectional communication network that links the central nervous system (CNS) to the enteric nervous system (ENS) of the gastrointestinal tract. In other words, it’s the connection between our brain and our gut.

The ENS is sometimes called our “second brain” because it contains more than 100 million nerve cells, which is more than the spinal cord!.

These two systems communicate with each other through a variety of signals, including hormones, peptides, and neurotransmitters.

The gut-brain axis also involves the immune system and the microbiome, which refers to the trillions of bacteria, fungi, and other microorganisms that live in our gut.

The Role of the Microbiome in Brain Health

The microbiome plays an important role in the gut-brain axis, and research is starting to uncover just how significant this role is.

One study, for example, found that people with depression had lower levels of two specific types of bacteria in their gut – Coprococcus and Dialister – as well as higher levels of a type of bacteria called Actinobacteria. Another study found that people with irritable bowel syndrome (IBS) had lower levels of several beneficial bacteria in their gut, including Bifidobacterium and Faecalibacterium.

But how exactly do these bacteria impact our brain health? One theory is that they influence the production of neurotransmitters, which are chemicals that transmit signals between neurons in the brain.

For example, the bacteria Lactobacillus and Bifidobacterium have both been shown to increase levels of the neurotransmitter GABA, which can help reduce anxiety, while other types of bacteria – such as Escherichia coli – can increase levels of the stress hormone cortisol.

The Gut-Brain Axis and Stress

Speaking of stress, the gut-brain axis is also closely linked to our stress response. When we’re under stress, our body releases hormones like cortisol and adrenaline, which can affect our digestion and gut motility.

On the flip side, problems with our gut – such as irritable bowel syndrome – can actually lead to increased feelings of stress and anxiety.

Researchers have also found that the bacteria in our gut can play a role in how we respond to stress.

One study, for example, found that mice that were given a specific strain of Lactobacillus had lower levels of stress and anxiety when placed in a stressful situation. Another study found that people who took a daily probiotic supplement for four weeks had lower levels of the stress hormone cortisol compared to a control group.

How to Support a Healthy Gut-Brain Axis

If you’re interested in improving your gut-brain axis – and who isn’t? – there are several things you can do to support a healthy microbiome and promote good brain health:.

1. Eat a balanced diet.

The foods we eat can influence the types of bacteria that live in our gut. Aim for a diet high in fiber, which can help feed beneficial bacteria.

You may also want to consider incorporating fermented foods – like yogurt, kimchi, and sauerkraut – which contain live, active cultures of beneficial bacteria.

2. Take a probiotic supplement.

While research is still ongoing, some studies have suggested that taking a probiotic supplement may help improve gut health and reduce symptoms of anxiety and depression.

Look for a supplement that contains a variety of bacterial strains and take as directed.

3. Manage your stress.

Since stress can impact both our gut and our brain, finding ways to manage stress is key. Try relaxation techniques like deep breathing or meditation, and make time for activities that you enjoy.

4. Get enough sleep.

Sleep has been shown to play an important role in the gut-brain axis, with one study finding that lack of sleep can actually lead to changes in our gut microbiome. Aim for 7-9 hours of sleep each night to support optimal brain and gut health.

Wrapping Up

The gut-brain axis is a complex system, and research is ongoing to fully understand how it works. However, what we do know is that there is a direct link between our gut microbiome and our brain health.

By taking steps to support a healthy microbiome – like eating a balanced diet, taking a probiotic supplement, managing stress, and getting enough sleep – we can potentially improve our brain health and overall well-being.